Shadow effect weakening based on intrinsic image extraction with effective projection of logarithmic domain for road scene

The accuracy of road region extraction is an important factor for the safety and reliability of intelligent driving system. Due to the shadow greatly affects the result of road region extraction in practical applications, the shadow effect weakening on a single image by the optical principles and theories is meaningful. To weaken the shadow effect, we extract the intrinsic images of road scenes based on logarithm domain projection. The intrinsic image has an advantage to remove the shadow effect. Thus, we propose effective projection angle calculation methods in logarithmic domain based on simple statistic, which can eliminate the impact of the direction of camera features. Furthermore, the best whole time projection angle with practical application can be obtained for rapid acquisition of intrinsic image. In the experiment, the proposed methods can weaken the shadow effect for road scene images. In order to evaluate intrinsic image extracted by the proposed methods, the same road detection method is implemented to extract road region. The results demonstrate that the road region detection accuracy based on intrinsic image extracted by our methods are better than the compared methods.